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Date:   Fri, 16 Aug 2019 14:04:10 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Jerome Glisse <jglisse@redhat.com>
Cc:     Jan Kara <jack@suse.cz>, Vlastimil Babka <vbabka@suse.cz>,
        John Hubbard <jhubbard@nvidia.com>,
        Ira Weiny <ira.weiny@intel.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Christoph Hellwig <hch@infradead.org>,
        Dan Williams <dan.j.williams@intel.com>,
        Dave Chinner <david@fromorbit.com>,
        LKML <linux-kernel@vger.kernel.org>, linux-mm@kvack.org,
        linux-fsdevel@vger.kernel.org, linux-rdma@vger.kernel.org
Subject: Re: [RFC PATCH 2/2] mm/gup: introduce vaddr_pin_pages_remote()
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On Fri, Aug 16, 2019 at 12:54:45PM -0400, Jerome Glisse wrote:

> > Yes, I understand. But the fact is that GUP calls are currently still there
> > e.g. in ODP code. If you can make the code work without taking a page
> > reference at all, I'm only happy :)
> 
> Already in rdma next AFAIK so in 5.4 it will be gone :)

Unfortunately no.. only a lot of patches supporting this change will
be in 5.4. The notifiers are still a problem, and I need to figure out
if the edge cases in hmm_range_fault are OK for ODP or not. :(

This is taking a long time in part because ODP itself has all sorts of
problems that make it hard to tell if the other changes are safe or
not..

Lots of effort is being spent to get there though.

Jason